Rotary bit.



E. DOUBLE.

ROTARY BITl APPLICATION FILED IuIIE I?. 1914.

Patented May 9,1916.

I 7 6 1I 9 ,o 3 8 .f i l 'Roanne nur.

rieasaa v l -Specication ot Letters Patent.

Patented May 9, i916.

Application filed 'une 17, 1914. Serial No. $5,532.

To all whom 'it may concern:

Be it known that l, EDvvAnD` DOUBLE a citizen'ofthe United States, residing atl os Angeles, in the county ofLos Angeles and Y@ State of California, have invented a new and useful Rotary'Bit, of which the following is a specification.. In rotary bits in which a Vplurality of rotary cutters are mounted on thelower end of thel body, the cutters being inclined so that their cutting portions come rather 'close` together, it is found that the detritus is apt in some formations to accumulate underneaththe body between the 'cutters and'form an impediment to the free downward pas-A present invention to provide a novel and effective means for obviating this d iculty.

i Referring to the; drawings: Figure 1 is f au a side elevation of abit constructed vin accordance with my invention. Fig.A v2. is a l longitudinal sectionalview through the bit. Fig. 3 is an end elevation of the lower 'end of the body. VlligLflL-is, a side elevation'in detail of one of the cutters.

1 designates the drill body provided with a tapered lower end on which are rotatably mounted a plurality of cutters 2 in such a manner that the cutting edges. ofthe cutte ters' come ratherV close togetherv at the bot- \tom. In the present caselhave shown two cutters 2, arranged oppositev each other, but thepreclse number of cutters employed 'is immaterial to .the ,inventienr l have found 1in practice that the detritus isin some formations apt to collect between the lower cutting edges ofthe cutters underneath the body 1, and pack therein to a greater or less extent, and''fthereby prevent the freet@ downward movement. Detritus is aptJ to pack therein in such a manner as to make it didicult to dislodge it in the usual manner by the entering stream of water which Hows downthrough the cutters 3 formed in the body 1, and discharges from branches 4r at the lower end of the body 1. The feature of the present invention is to consttuct the cutters 2 with openings or perforaticns therein at such a point as to allow the detritus which lodges in the space between the cutters to be discharged laterally outward through the openings 1n the cutters by being washedtherethrough by the entering stream of water from the water courses 4. The enact form and arrangement of theperforations is immaterial. lln the present case l have shown an outer row of perforations 5 and an inner row of larger perforations 6. These perforations are preferably with tapering walls 7, the smaller diameter of which is on the inside of the cutter; so that material which. 1s forced into the inner end of the perforation will readily passthrough then perforation without packing therein 'as the diameter of the perforation increases toward the outer ends.

lln the present case the with plain circular cutting edges 8, but the exact form of cutting ed e is not essential. As before stated, the detritus is apt to pack `between the cutters at a point above thev sage of the tool, and it is the object 'of the cutting edges thereof, and for this reason cutters are shown the perforations are preferably arranged at a polnt inward from the cutting edge lof the cutters suiiicient to receive the detritus from points above the cutting edges.

` By constructing. thecutters in this manner with-numerous small perforations, the nec essary openings are Yproduced for the pas-v sage of detritus without weakening the cutters, and the bit as thus constructed will operate freely in all formations without the, detritus choking into the space between the cutters and retarding the progress of the drill.

' Ilhe manner in which the cutters 'are se cured t'o the bodyis immaterial; ln the drawings l have, shown the cutters as `mounted on studs 9, which are screwed in v the body 1,'and are locked in place byy a) curved 'bolt 10` which passes completely through both studs 9. 'The cutters are preferablymoun'ted on bushings 10 withwash` ers 11 and l2 arranged on both sides of vthe bushings.

What I claimis:

1.111 a rotary bit', a body with a wedge shaped lower end, la pair of rotatable cutters mounted on the lower end with' the loweredges of the cuttersclose together-thebody being'providedwith a water coursefor conducting -water into the space between ysaid cutters at thelowerend of the body, said cutters being provided with perforations topermit the passage of detritus from' said space directly outward through the cutters.

2. ln-a rotary bit, a body and rotatable' cutters mounted on the lower end of the body and having their lower ends closer tov yeach other than their upper ends, said body having a water course therein discharglng between the cutters, said cutters having perl below the lower end thereof between the,-

forations therein to permit vthe passage of detritus from the space between the cutters.

3. In a rotary bit, a body and rotary cutters`mounted on the lower end of the body and projecting below the lower end thereof, said cutters having perforations formed therethrough communicating the outer faces thereof with thespace below the lower end of the body between the cutters, and said body having a water passage formed' therein discharging into the space cutters.

4. In a rotary bit, a body and rotary cutters mounted on lthe lower end of the body and projecting below the lower end thereof, said cutters having, `perforations formed therethroughommunicating the outer faces thereof with the space below the lower endl of the body, between the cutters, and said b dy having a water passage formed therein discharging into the space below the lower end thereof between the cutters, lsaid cutters having their lower ends located in closer relation to one another than their upper ends.

5. In a rotary bit, a body. and rotary cutters mounted on the lower end of the bodyl and projecting below the lower end thereof,

saidcutters having .openings formed therethrough communicating thereof with the space belowithe body and the outer faces f between the cutters, said openings being,

tapered and enlarged at their outer ends,

said body having a water course thereof the bodybetween the cutters, one/of said rows of openings being larger than the other, and said body having a Water course therethrough discharging between the cutters below the lower end of the body.

' Intestimony whereof, I have hereunto set my hand at lLos 'A ngeles, California, -this 12th day of'June, 1914.

EDWARD DoUBnE.-

presence ofv LORA M. BOWERS,

LORRAINE E. DUnow.- 

